Adjacent channel interference caused by intermodulation distortion adversely affects the network operations in next generation heterogeneous and dynamic spectrum access networks. Multitudes of radio access technologies make the receivers susceptible to harmful interference due to nonlinear RF front ends. In this paper we analyze the intermodulation distortion arising from pairwise interactions of adjacent channel signals from a spectrum centric point of view and develop frameworks to ascertain the adjacent channel signals causing interference at a given desired channel. We further propose achievable schemes for interference avoidance and assess the scalability of the next generation Nonlinear Adjacent Channel Interference Networks. We further propose schemes for complete interference protection of incumbents with sensitive receiver requirements from secondary operations in adjacent channels in the spatio-temporal vicinity. This paper presents valuable insights on scalability and schemes for nonlinear adjacent channel interference avoidance in next generation shared spectrum networks.